Anna-Lisa Newman credits support from peers and advisers for the success of a new pasture legume-crop rotation she and her husband Craig have established, transforming their low to medium-rainfall mixed farm at Varley in Western Australia.
The Newmans were involved in the Dryland Legume Pasture Systems (DLPS) project, supported by GRDC, which has driven novel hard-seeded pasture legume adoption in these regions.
“Through DLPS on-farm trials we learnt how to establish these species and really make them work in our farming system,” Anna-Lisa says. “We now benefit from improved organic nitrogen and overall fertility, and nitrogen fertiliser savings, demonstrated in continued yield improvements.
These trials also created evidence of livestock nutritional gain by grazing these new species.
In 2014, the Newmans’ 3400 hectares only had 27 per cent of inconsistent subterranean clover or medics.
“We have steadily purchased more land over the years but none of it had established pastures,” Anna-Lisa says. “In 2015, we made an ambitious plan to address large areas lacking pasture legumes, as we clearly saw a lack of legumes was affecting both cropping and livestock phases.”
The Newmans’ Karradale Trading property is 420 kilometres south-east of Perth. Soil types on their now 8300ha are split between duplex sands/clay soils and gravely ironstone; pH ranges from 5.0 to 6.5. Their business is 60:40 per cent cropping and grazing, with 4800 self-replacing multi-purpose Merino ewes and a mix of barley, oats, canola and wheat.
Average annual rainfall is about 323 millimetres. Effective rainfall is 183mm and decreasing, but summer rainfall is increasing.
Given the large scale of the renovation project, finding easily grown, harvested and then resown species was a big part of our decision as there were significant savings in producing our own seed.
“Likelihood of successful establishment in the first year, regeneration in subsequent seasons and finally biomass were also important considerations, especially in dry seasons. Consequently, we selected mostly serradellas – hard-seeded Margurita and Fran2o varieties dominate as they are suited to our widespread acidic gravelly sands.
“For heavier soils we use a small amount of clover and biserrula. Our preference is biserrula as, despite being a difficult seed to harvest, it is incredibly hardy and endures tough seasonal conditions. Both serradella and biserrula have extensive taproots that aid survival.
“We establish serradellas using novel summer sowing, and biserrula closer to the seasonal break. The establishment phase calls for two pasture phases in three years to renovate run-down pastures and now we achieve two years crop to one year pasture in rotation.”
She says the biggest challenge was initially gaining confidence in how the system would work and getting started.
“Staying confident was then challenging as we hit hurdles along the way, but with now over 6000ha of regenerating legumes in place since 2016, it has been worth it. Being supported through the DLPS with advice and connections to other growers who were successfully growing the species or producing available seed helped.”
The DLPS project is part of the Federal Government Department of Agriculture, Water and the Environment’s Rural R&D for Profit program.